Solid solution silver iodide

A slight excess of a 10% sodium hydroxide solution was added to a solution of 23 grams of silver nitrate in 300 cc of water. The precipitated silver oxide was washed free of silver ion with distilled water. To a suspension of the silver oxide in 200 cc of water, a solution of 25 grams of (3-hydroxyphenyl)ethyl dimethylammonium iodide in 300 cc of water was added. The precipitate of silver iodide was removed by filtration and the filtrate concentrated to a volume of about 100 cc In vacuo. The remainder of the water was removed by lyophilization. (3-hydroxyphenyl)ethyl dimethylammonium hydroxide was obtained as a hygroscopic, amorphous solid,... 

Silver iodide is very insoluble in water. A common method for increasing its solubility is to increase the temperature of the solution containing the solid. Estimate the solubility of Agl at 85°C. 

Filtering and Drying the Silver Halide.—First heat the precipitate in the beaker on the boiling water bath. Heat silver iodide (and bromide) for two hours, since silver iodide forms with silver nitrate a solid compound which is only gradually decomposed by water. Further, when determining iodine, first reduce with sulphurous acid solution the silver iodate produced during the decomposition. 

POLYMORPHISM. 1, A phenomenon in which a substance exhibits different forms. Dimorphic substances appear in two solid forms, whereas trimorphic exist in three, as sulfur., carbon, tin, silver iodide, and calcium carbonate. Polymorphism is usually restricted to the solid state, Polymorphs yield identical solutions and vapors (if vaporizable). The relation between them has been termed physical isomerism. See Allotropes under Chemical Elements, See also Mineralogy,... 

For an interface such as silver iodide-electrolyte solution the electric potential difference between the solid interior and the bulk solution varies according to the Nernst equation ... 

Faraday s law holds for solid electrolytic conductors as well as for fused electrolytes and solutions this is shown by the results of Tubandt and Eggert (1920) on the electrolysis of the cubic form of silver iodide quoted in Table III. The quantities of silver deposited in an ordinary... 

Coulometric determinations of metals with a mercury cathode have been described by Lingane. From a tartrate solution, copper, bismuth, lead, and cadmium were successively removed by applying the appropriate cathode potential, which was selected to correspond to a region of diffusion-controlled current determined from current-voltage curves with a dropping mercury electrode. With a silver anode, iodide, bromide, and chloride can be deposited quantitatively as the silver salt. By controlling the anode potential, Lingane and Small determined iodide in the presence of bromide or chloride. The separation of bromide and chloride, however, was not successful because solid solutions were formed (Section 9-4). 

We have described the series of reactions that occurs when solid AgN03 is added slowly to a solution that is 0.0010 M in C1-, Br-, and f-. Silver iodide begins to precipitate first 99.955% of the precipitates before any solid AgBr is formed. Silver bromide begins to... 

The surface charge on a solid surface can be obtained by determining the adsorption of potential-determining ions at various potentials of the interface [1]. For example, in the case of a silver iodide sol the adsorption of Ag+ and I ions is determined at various concentrations of Ag" " and I" ions in bulk solution. Similarly, for an oxide the adsorption of H" " and OH" ions Fand respectively) is determined as... 

A compound of iodine that deserves mention is silver iodide, Agl. It is a pale-yellow solid that darkens when exposed to light. In this respect it is similar to silver bromide. Silver iodide is sometimes used in cloud seeding, a process for inducing rainfall on a small scale (Figure 21.21). The advantage of using silver iodide is that enormous numbers of nuclei (that is, small particles of silver iodide on which ice crystals can form) become available. About 10 nuclei are produced from 1 g of Agl by vaporizing an acetone solution of silver iodide in a hot flame. The nuclei are then dispersed into the clouds from an airplane. 

Silver iodide (K p = 8.51 x 10 ) is less soluble than AgCl in aqueous solution, and so reduction of Ag(I) in the form of solid Agl is thermodynamically less favourable than reduction of AgCl (see problem 7.11 at the end of the chapter). However, Agl is much more soluble in aqueous KI than AgCl is in aqueous KCl solution. The species present in the iodide solution is the complex [Agl3] , the overall stability constant (see Section 6.12) for which is sslO " (equation 7.32). Following a similar procedure to that detailed above, we can use this value to determine that the... 

One may effectively control the stability of atmospheric aerosols by spraying concentrated solutions of hygroscopic substances, such as calcium chloride, or solid substances, such as silver iodide and solid carbon dioxide. These substances cause condensation of water vapor (or the formation of small ice crystals in supercooled clouds), and result in precipitation. Analogous means can be used to dissipate fog. 

Silver Iodide. Silver iodide, Agl, precipitates as a yellow solid when iodide ion is added to a solution of silver nitrate. It dissolves in the presence of excess iodide ion, forming an Agl2 complex however, silver iodide is only slightly soluble in ammonia and dissolves slowly in thiosulfate and cyanide solutions. 

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